Chemical retention

Solutions of these fire retardant formulations are impregnated into wood under fliU cell pressure treatment to obtain dry chemical retentions of 65 to 95 kg/m this type of treatment greatly reduces flame-spread and afterglow. These effects are the result of changed thermal decomposition reactions that favor production of carbon dioxide and water (vapor) as opposed to more flammable components (55). Char oxidation (glowing or smoldering) is also inhibited. 

Chemical Retention in the Ground. Due to chemical interac-tions with the rock and with species in the groundwater the radionuclides will be retarded. This would be the final barrier preventing a release into the biosphere. 

Treatment of the lumber by either of the above preservatives shall be in accordance with the American-Wood Preservers Association Standards Cl and C2 for Pacific Coast Douglas Fir, except that the lumber shall not be incised. The empty- and full-cell process shall be used for the Creosote and waterborne preservative treatments, respectively. Treatment shall be guaranteed to the extent that the average chemical retention will be as stated above. 

The untreated plywood had a flame-spread index of 115. This was reduced to about 55 at a chemical retention of 2 pounds per cubic foot, to 35 at 3 pounds, 20 at 4 pounds, and to about 15 at retentions of 4.5 pounds and higher. Zinc chloride was next in effectiveness but required higher retention levels to reduce the flame-spread index values equivalent to monoammonium phosphate. 

Figure 2. Relationship of flame spread to level of chemical retention in 3/8-in. Douglas fir plywood evaluated by the 8-ft tunnel furnace method...

Equation (8-3) is used to determine k values for experiments A-C, as indicated in the table. The Vr values for the dyes in this experiment are the volumes corresponding to the centers of the red and blue bands. No value is measured for Em, however. The best method for obtaining a true value of Em is to inject on the column a compound that is very similar, in chemical retentivity to the mobile phase and that responds to the detector. Such a compound would be unretained by the stationary phase and would elute after passing through the volume Em which is occupied by the mobile phase within the column. Due to the limitations of the apparatus used in these experiments, we will approximate Em- For a column filled with porous packing, the value of Em represents about 50% of the total empty column volume and can be estimated by the equation... 

When a chemical solution is injected into a reservoir at interstitial water saturation, due to chemical retention, a denuded water zone is formed at the injection front, which causes a chemical shock at x 3, as shown in Figure 2.15. This chemical shock causes the saturation shock from 8 3 to 8 1 at x 3. The denuded water displaces the interstitial water. There is a boundary between the denuded water and the displaced interstitial water at x b. 

Absorption an irreversible chemical retention effect on surfaces, either liquid or solid. Improperly applied to the dissolution (physical effect) of gases in liquids. 

Unfortunately, the fibre network structures formed during filtration on the wire are not small-scale enough to retain the finer materials, which are also needed in order for the paper to have the desired properties and prevent buildup in the white water of fillers and fines. In the design of chemical retention systems, it is important to strive for efficient bonding of smaller-sized materials, while keeping the fibres from forming large floes and non-uniform lateral properties. 

Waterproof boots, or security shoes, can protect the skin of the lower legs, ankles, and feet. At the opposite, when contaminated, they can be a source of chemical retention at lower body parts. In such... 

Advantages of single inverted 5-spot are its low cost, which enables the determination of injectivity and a rough estimate of mobility control, oil mobilization, and chemical retention. In addition, it provides production experience and fast results. The disadvantages include the following ... 

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